Fire-extinguisher composition.



HARRY S. MORE, BROGKLINE, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGE-MEETS, T0 AMERICAN LA FRANCE FIRE ENGINE CO'MPANY, ING, OF EL'MIRA, NEX

YDRK, A CDEPQBAIIQN 0 NEW YORK.

Ito Drawing.

To all? whom a; may concern Be it known that 1, linear S. Moms, a

citizen of the United States, residing at lBrookline, county of Norfolk,State ct Mas sschusetts, have invented a. certain new and usefulFire-Extinguisher Uomposition, of which the following is aspecification.

My invention relates to fire extinguisher charges and more-particularlyto the carbonnie solution from; which carbon dioxid for expelling theextinguishing medium is generated by reaction with a suitable acid.Alkali metal salts of carbonic acid, in the form of bicarbonate or inthe form of the normal carbonate have been commonly employed for suchsolutions, While sulfuric acid or hydrochloric acid has usually beenemployed as the acid charge. In order that the carbonate solution mayalways remain in e condition suitable for use even when exposed to lowtemperatures, it has been proposed to incorporate in the carbonatesolution, an ingredient for lowering the freezing point thereof. Most ofthose ingredients which have been heretofore proposed for this purposeare subject to one disadvantage or another. In some instances, theaddition agent tends to give rise to the formation of a precipitate ofinsoluble carbonate or other salt or to retard the generation orevolution of the carbon dioxid gas; or its effect in small quantitieshas not been sufficiently marked in depressing the freezing point.

The object of my invention is to produce a carbonate solution charge ofthe desired low freezing point which shall be free from thedisadvantages above noted. At the some time, the invention seeks toavoid the use of ingredients which might involve undue expense, or whichwould in any way interfere vwith the fire extinguishing qualities of themedium which is to be ejected from the apparatus.

The carbonate solution embraced by the present invention. comprises asessential ing edienls. an alkali metal salt of carbonic liCltl.preferably sodium bicarbonate, and an alkali metal citrate, especiallypotassium citrate. To clearly illustrate the principles involved and toenable those skilled in this ill'tto understand and practice theinvention, l may refer to e-specific-exnmple in which the solutioncomprises sodium bicarbonate and potassium citrate crystals in substan-Speoification of Letters Patent}.

either Patented se t. in, 11918.

Application filed January 14, 1918. serial 260. 211,535.

tially the proportions 0155.53 grams of sodium bicarbonate and 107 gramsof poles slum citrate crystals in 100 cubic centimeters of weter. Such asolution has a freezing point close to- F. and remains quite fluid withconsiderable drop in temperature, becoming pasty at about -30 F. It isin all respects well adapted to serve as n lire tinguisher charge,although the capacity of the solution for developing carbon dionid gas,when treated with acid, is somewhat reduced, due to the presence of thecitrate.

In place of sodium bicarbonate, I may employ potassium carbonate withthe potassium citrate, in which event, the solution would comprise theseessential ingredients, for example in the following proportions: 4.54grams of potassium carbonate and 115 grams of potassium citrate crystalsin 100 cubic centimeters of water. This solution shows a freezing pointof approximately 5? E, crystals, however, being separated at -20 F, orat about that temperature.

Similar solutions may be made up for example of 4.54 grams potassiumcarbonate with 91 grams of sodium-citrate; 6.6 grams of potassiumbicarbonate with 105.9 grams potassium citrate; or 5.21 grams ammoniumbicarbonate with 106.5 grams potassium citrate. These proportions assumethe presence of 100 c. c. of Water, and are intended to be onlyillustrative of the general principles involved. It is to be noted thatthe capacity of the potassium carbonate solution for setting free carbondioxid gas, when treated with acid, appears to be somewhat improved bythe presence of the sodium citrate inthe example given. The carbonatesolution embodied by the present invention is adapted to be em .oyed inthe usual manner as a charge for re extinguishers, wherein it is actedupon by a. suitable acid for developing the carbon dioxid gas by whichthe fluid is expelled upon the fire, I claim: 1. A carbonate solution.for fire extinguishers, comprising as essential ingredients,

an alkali metzil salt of carbonic acid, and an guishers, comprising asessential ingredients,

sodium bicanbonate and an alkali metal citrete.

3. A carbonate solution for fire extin' guishers, comprising asessential ingredients, guishers, comprising as essential ingredients,sodium bicarbonate andpotassiumcitrate, w analkali metal salt ofcarbonic acid, and posubstantially in the proportions of 5.53 tassiumcitrateQ grams of'sodium bicarbonate and 107 grams in A carbonatesolution for fire extinof potassium citrate in 100 cubic centimetersguishers, comprising as essential ingredients. of water. a sodiumbicarbonate and potassium citrate.

5. A carbonate solution for fire extin- HARRY S. MORK.

